Controlled depth primer tool



April 11, 1967 E. E. LAWRENCE I CONTROLLED DEPTH PRIMER TOOL 2 Sheets-Sheet 1 Filed April 22, 1965 April 1, 1967 E. E. LAWRENCE 3,313,201

CONTROLLED DEPTH PRIMER TOOL 2 Sheets-Sheet 2 Filed April 22, 1965 INVENTOR Wye/ 640? ATTORNEY United States Patent Office 3,313,201 CONTROLLED DEPTH PRIMER TOOL Elmer E. Lawrence, RR. 2, Hayward, Wis. 54843 Filed Apr. 22, 1965, Ser. No. 450,058 8 Claims. (CI. 86-32) This invention relates generally to a primer tool, and more particularly, to a manually actuated apparatus for removing spent primers and applying new headless or rimless primers to metallic rifle and pistol cartridge cases whether of the rim or rimless type.

Many devices have been constructed to perform the dual function of applying new primers to cartridge cases as well as removing therefrom the spent or used primers. However, these prior devices for the most part have comprised numerous complicated parts requiring constant readjustment and all too often resulted in improper seating of the new primers in the cartridge cases.

For the most part these known reloading presses include a shell holder having a transverse slot into which the rim of the case is slid and thus the sole support for the case is through this rim area. In pressing in a new primer with these devices a ram is actuated and the control of this seating pressure is by the operators sense of touch only as no positive stop control is provided. Another shortcoming of many prior devices is that after depriming the case, it is impossible to visually inspect the area of the flash hole as the case is often partially inac cessible to the operators view.

No known simple lightweight tool is available which is particularly adapted for use as a bench tool and is designed to be manually actuated for precisely seating primers to the exact depth specified for the particular metallic case being operated upon. known devices have relied upon the thickness of the rim and the adjacent rear face of the case to determine the limit of travel of the plunger used during the seating of the primer into the primer pocket of the case. It is not uncommon when using such devices for the case rims to become badly deformed. In such instances, the primers can only be seated to a fixed depth within the case and it is well known that the thickness of the case rim varies considerably between various manufacturers, each of which has selected his own set of tolerances.

The proper seating of a primer in a cartridge case cannot be overemphasized. The level of sensitivity of all primers can be destroyed by improper seating. The primer ignition is a result of a crystal reaction to the force of a sudden blow or shock or initiated by a firing pin. This crystal reaction, more properly known as sublimation, is a reaction whereby the crystal transfers directly into a gaseous state from a solid state. This process is extremely rapid. Accordingly, it will be realized that a high percentage of misfires or hang-fires will be realized due to the improper seating of primers such as would be the case if the primer were driven too deeply into the primer pocket in the base of the case, or on the other hand, not driven in far enough. The primers comprise a cup containing a cake-like mixture of a wellknown ignition initiator such as lead styphnate, and include a substantially V-shaped anvil, the point of which projects into the ignition initiator with the legs thereof directed outwardly to the mouth of the cup. Only when the primer is properly seated within the cartridge case, will the legs of the anvil make contact with the bottom of the primer pocket so that the point of the anvil will be forced by a few thousandths of an inch into the priming mixture in the cup. This placement results in the anvil resting solidly on the bottom of the pocket and causes a stress in the ignition initiator mixture by the point of the anvil which is a most important factor in arriving at the correct primer sensitivity. It is only with such Many of the prior 3,313,291: Patented Apr. 11, 1967 a properly seated primer that reliable firing can be obtained.

Not only will an improperly seated primer lead to a misfire or hang-fire, but should the primer actually be detonated, it is very likely that the ballistic properties of the projected bullet will be highly defective. The present invention overcomes the above shortcomings by providing a primer tool having means for positively controlling the depth of the seating plunger during the primer applying operation without dependence upon the thickness of the case rim and without the possibility of producing any damage to the casing during this operation.

Accordingly, one of the primary objects of the present invention is to provide a primer tool having means precisely controlling the depth of the primer seating operation.

Another object of the present invention is to provide a primer tool including adjustable means for limiting the degree of seating of a primer.

Still another object of the present invention is to provide a primer tool having means to properly seat a primer to an exact specified depth regardless of the thickness of the case rim.

A further object of the present invention is to provide a primer tool which is manually actuated and readily converted from a priming to a depriming operation.

Another object of the present invention is to provide a primer tool including means for automatically supplying new primers one at a time to the primer seat.

With these and other objects in view which will more readily appear as the nature of the invention is better understood, the invention consists in the novel construction, combination, and arrangement of parts, hereinafter more fully described, illustrated and claimed.

A preferred and practical embodiment of the invention is shown in the accompanying drawings, in which:

FIGURE 1 is a fragmentary sectional view of a typical cartridge case showing an improperly seated primer disposed therein.

FIGURE 2 is a fragmentary sectional view similar to FIGURE 1 but with a primer properly seated therein.

FIGURE 3 is a perspective view of a primer tool according to the present invention with a cartridge case shown removed from the seating plunger thereof.

FIGURE 4 is a transverse sectional view taken along the line 4-4 of FIGURE 3.

FIGURE 5 is a front elevation of the primer tool according to the present invention, with portions in section for purpose of clarity.

FIGURE 6 is a perspective view of the present invention showing the depriming punch in use therewith.

Similar reference characters design-ate corresponding parts throughout the several figures of the drawings.

By means of the present invention, cartridge cases may be loaded with primers which are press-fitted into the base of the case to the exact depth as specified according to the particular manufacturer of the case in order to ensure maximum sensitivity of the primer to detonation. As will be seen in FIGURES 1 and 2, a typical cartridge case, generally designated C, includes a recessed portion 1 terminating in an outwardly projecting rim 2 which is adjacent a rear face 3. Axially disposed within the face 3 of the case is a primer pocket 4 :for the reception of the primer 5. The primer cap comprises a cup member containing an ignition initator 6 and a substantially V- shaped anvil 7.

FIGURE 1 illustrates a primer which has been improperly seated such as would be the case with many of the prior known primer tools which rely upon the face and rim of the cartridge case to determine the limit of the stroke during the pressing operation wherein it will be seen that the top inner flange of the cup member is not bottomed out within the primer pocket 4. With this condition, the point of the anvil 7 is not driven into the ignition initiator 6 in order to place it under the proper stress to ensure maximum sensitivity.

FIGURE 2 illustrates a properly seated primer wherein it will be seen that the cup member is fully seated within the primer pocket 4, and the legs of the anvil 7 have been driven entirely within the confines of the walls of the primer cup so that the point of the anvil is sufiiciently driven into the ignition initiator 6 to place it under the required stress. The novel controllable depth feature of the present invention ensures the proper seating of the primer as shown in this figure wherein it will be seen that the exposed face of the primer cup is recessed beyond the outer plane of the face 3 of the cartridge case.

As will be seen from FIGURE 3, the primer tool of the present invention comprises a manually operated device having a tool support plate 8 adapted to be disposed upon a bench. Fixedly attached to the plate 8 are a pair of vertically disposed parallel pillars 9 and 10, each having a threaded lower portion which is screwed into tapped openings in the plate. To facilitate the ready assembly and disassembly of pillars 9, 10 with respect to the plate 8, each of the pillars is provided with a transverse diametrical bore 11 adjacent the lower end thereof for the reception of a suitable elongated tool providing adequate leverage for turning the pillars into and out of the tapped openings in the plate 8.

A guide bushing slide 12 is mounted for vertical reciprocating movement upon the two pillars 9 and 10 and includes a medially disposed counter-sunk opening 13 for the reception of a guide bushing 14, as will be most clearly seen in FIGURE 5. The guide bushing 14 includes a central body portion 15 and a raised shoulder portion 16 having a larger outer diameter than the body portion 15. The top of the guide bushing is counter-sunk or recessed to provide a cartridge case seat 17 having a diameter adapted to provide a close fit for the face 3 and rim 2 of the particular cartridge case C being operated on. A radial cutout 18 is provided through the raised shoulder portion 16 of the guide bushing 14 for the reception of a feed tube supplying primers to the bushing as will be described hereinafter. It will be understood that a close fit is provided between the lower outer surfaces of the shoulder 16 and the periphery of the central body portion 15 and the adjacent surfaces of the counter-sunk opening 13 in the guide bushing slide 12 in order to preclude the radial displacement of the guide bushing during operation of the primer tool. For the purpose of securely retaining the guide bushing 14 in its operative relationship within the slide 12, the outer circumference of the central body portion 15 is provided with a peripheral groove 19 into which may be tightened a suitable lock screw such as shown at 20 in FIGURE 3. A cylindrical primer aperture 21 extends axially through the entire vertical height of the guide bushing 14.

A pair of stop collars 22 and 23 slidably disposed upon the pillars 9 and 10, respectively, are locked thereto by means of set screws 24 and 25 to limit the upward travel of the guide bushing slide 12 and obviously will be secured to the pillars in a manner to ensure that when the slide abuts against the undersurface of the collars, it will be disposed in a true horizontal position. A pair of coil springs 26 and 27 are slidably disposed around each of the pillars 9 and 1t and bear on the one hand against the top of the plate 8, and on the other hand against the undersurface of the guide bushing slide 12 to urge said slide in a normal upward position against the undersurface of the stop collars 22 and 23 as shown in FIGURES 3 and 5.

A tapped opening 28 in the support plate 8 is axially disposed irnmediately beneath the primer aperture 21 in guide bushing 14 for the reception of a stop nut screw 29 therein. Projecting upwardly from the stop nut screw 29 is a cylindrical primer stem 30 which provides a close sliding fit within the primer aperture 21 while disposed over the primer stem 30 and engaging the threads of the stop nut screw 29, is an adjustable guide bushing stop nut 31. It will thus be understood that manual rotation of the stop nut 31 upon the screw 29 alters the vertical disposition of the stop nut 31 to thus limit the permissible downward movement of the guide bushing 14 mounted in the guide bushing slide 12 thereby providing precise means for controlling a relative location of the primer stem 30 with respect to the guide bushing 14 to achieve exact positioning of new primer caps within the primer pockets of the cartridge cases being operated upon.

The upper portions of the pillars 9 and 10 are connected together by means of a transverse top bridge 32 which is retained in position by means of a pair of nuts 33 and 34.

The actuating mechanism for achieving the priming and depriming operation is suspended from an intermediate portion of the top bridge 32. This structure includes a seating plunger 35 comprising a cylindrical rod adapted to freely pass through the neck portion 36 of the cartridge case C. The upper end of the seating plunger 35 is preferably screw fitted into a pivotal union 36 as shown in FIGURE 5, the pivotal union in turn being connected by means of the pin 37 to the bifurcated portion of a plunger drive rod 38, slidably disposed through the top bridge 32.

An actuating handle 39 is employed for imparting vertical movement to the seating plunger 35 and has one end thereof connected as at 40 to a pivoting connecting link 41 which in turn is pivotally attached to a bifurcated anchor bolt 42 secured to the top bridge 32. As most clearly shown in FIGURE 5, the top extremity of the plunger drive rod 38 is pivotally connected to the plunger actuating handle 39 at a point adjacent to the handle pivoting point 40 and is normally biased to an uppermost position by means of a coiled plunger return spring 43 surrounding the drive rod 38. The upper travel of the plunger drive rod 38 will be limited by the outwardly extending portion of the pin 37 joining the drive rod 38 to the pivotal union 36.

As will be seen in FIGURES 3 and 5, the union 36 and drive rod 38 are axially aligned above the primer aperture 21 and are positioned such that the seating plunger 35 may be swung outwardly so that its lowermost end may be disposed away from the guide bushing slide 12 as in FIGURE 3 for the insertion and removal of a cartridge case C. Following the mounting of a cartridge case upon the plunger 35, the assembly is returned to a vertical position and the rim 2 of the case disposed within the cartridge case seat 17 of the guide bushing 14, whereafter, the face 3 of the cartridge case will rest entirely within the raised shoulder portion 16 of the guide bushing. With a new primer 5 having been previously deposited within the primer aperture 21 of the bushing and resting upon the top of the stem 30, it will be seen that it is a simple matter to accurately and completely seat the primer within the primer pocket 4 of the cartridge case C by the application of downward force upon the end of the plunger actuating handle 39, which downward force will be transmitted with a high degree of mechanical advantage through the plunger drive rod 38 to the seating plunger 35. This force is in turn delivered from the bottom portion of the plunger 35 through the bottom of the case C to the cartridge case seat 17 of the guide bushing. As the guide bushing is driven downwardly against the force of the slide springs 26 and 27, the primer pocket 4 of the case will envelop the primer cup 5 and continued downward movement of the seating plunger 35 will cause the primer stem 30 to drive the primer into the case primer pocket, the limit of this operation automatically being controlled by the abutment of the bottom surface of the guide bushing 14 upon the upper surface of the adjustable guide bushing stop nut 31, it being understood that said stop nut has been accurately positioned upon the stop nut screw 29 in order to achieve a properly seated primer such as illustrated in FIGURE 2 of the drawings.

The present invention includes supply means for automatically delivering new primers one at a time to the primer aperture 21 of the guide bushing 14. This means comprises an oscillating primer delivery arm 44 which is movably mounted about the vertical pillar 9. The delivery arm 44 is supported upon the stop collar 22 and pivotally retained thereupon by means of a retention collar 45 disposed about the pillar 9 above the delivery arm, in a position assuring slidable oscillating movement of the delivery arm between the collars 22 and 45. Mounted through the outer free end of the delivery arm 44 is a bushing 46 having a central aperture for the reception of a hollow primer feed tube 47 which may be securely retained within the bushing 46 by means of a set screw 48 thus permitting relative vertical adjustment of the feed tube in order to achieve the desired operation as will be described immediately hereinafter.

The internal diameter of the feed tube 47 is designed for the slidable reception of primers which are initially fed into the tube in a stacked relationship. The normal standby position of the primer cap delivery mechanism is as shown in FIGURE 4 wherein it will be seen that oscillatory movement of the delivery arm 44 is limited in this position by means of a vertically disposed stop plate 49 which stop plate extends upwardly from a base attaching arm 50 secured by any suitable means to the tool support plate 8. Connected to the vertical stop plate 49 and extending in a substantially horizontal plane therefrom is a primer delivery ramp 51 having its free end in abutment with the rear periphery of the raised shoulder portion 16 of the guide bushing 14 as will be most clearly seen in FIGURE 4. The vertical feed tube 47 is positioned through the delivery arm 44 at a point which ensures that as the delivery arm is oscillated about the pillar 9, the lower portion of the feed tube 47 will describe an are passing not only through the cutout portion 18 formed through the Wall of the raised shoulder portion 16 of the guide bushing but will also pass directly over the primer aperture 21. To facilitate the oscillation of the delivery mechanism, a handle 52 is attached to the end of the delivery arm 44 opposite that through which the feed tube 47 passes. It will be understood that the clearance between the lowermost portion of the feed tube 47 and the top surface of the primer cap delivery ramp 51 is less than the vertical height of a primer so that as the delivery arm is oscillated, the lowermost primer in the tube 47 will be guided along the delivery ramp through the cutout portion 18 of the guide bushing until it is vertically disposed above the primer aperture 21 at which point the lowermost primer will fall by gravity into the aperture, finally resting upon the top of the primer stem 30. It will be obvious that the end of the delivery ramp 5-1 adjacent the cutout portion 18 of the guide bushing is disposed substantially coplanar therewith so as not to hinder the smooth guiding of the primer cap across the juxtaposed surfaces, and it will be seen that by the rapid oscillation of the delivery arm, only the lowermost primer will be permitted to drop into the aperture 21.

The present invention is readily adapted for the removal of spent primers from fired cartridge cases by a simple operation involving the substitution of a de-priming punch 52 for the seating plunger 35 and the application of a pair of rigid collars 53, 54, in place of the coil springs 26, 27, as shown in FIGURE 6. In view of the threaded connection between the seating plunger 35 and the pivotal union 36, the plunger may be readily disconnected from the tool by the application of any suitable elongated tool through the transverse diametrical opening 35a in the plunger concurrently with the application of a similar tool through the opening 36a in the union so that reverse forces may be applied to the two elements to unthread the plunger from the union. The de-priming punch 52 is provided with similar threads (not shown) at its upper extremity for connection to the union 36 and also includes a transverse diametrical opening 52a to facilitate the attachment or removal of the punch. The lower extremity of the punch 52 is provided with a downwardly projecting punch point 55 for pressing out the spent primer from the primer pocket of the casing C. Quite obviously, the adjustable guide bushing stop nut 31, as well as the stop nut screw 29, are removed from the tool support plate 8 when the tool is utilized for removing spent primers, and thereafter any suitable collection receptacle 56 may be placed beneath the guide bushing 14 for the reception of the spent primers as they are pressed out through the primer aperture 21.

A precautionary feature is provided in the lower portion of the plunger 35 to serve as a safety valve should a primer be accidently detonated during the seating operation. As shown in FIGURE 5, the bottom of the plunger is provided with a tapered or conical opening 35 connected through a drilled passage to the diametrical opening 35a. Should a primer detonate it will be seen that the gas will safely pass upwardly through the openings and thence through the mouth of the case. Also, the clearance provided in the bottom face of the plunger by the opening 3-5 eliminates the possibility of pushing any burrs which may exist in the case bottom over the flash hole which would obstruct the flash hole.

Although the present invention offers many advantages heretofore unavailable in a primer tool adapted for oper ating upon metallic pistol and rifle cartridge cases, it will be understood that the basic apparatus herein disclosed may be utilized for removing and applying primer caps to shotgun shells. Unlike the primers for pistol and rifle cartridges, primer caps for use with shotgun shells contain a peripheral flange or rim about the base and accordingly, there is no need to provide means for achieving a control seating depth since this is automatically achieved when the rim on the primer cap abuts the bottom face of the shotgun shell. Therefore, in order to utilize the present invention in operating upon a shotgun shell, it is only necessary to remove the fixed control means or stop nut as the operator Will know when the primer cap is properly seated as the rim of the primer cap abuts the bottom face of the shotgun shell.

It is to be understood that the invention is not limited to the specific features shown, but that the means of construction herein disclosed comprise the preferred form of several modes of putting the invention into effect and the invention is therefore plain in any of its forms or modifications within the legitimate and valid scope of the appended claims.

I claim:

1. An apparatus for applying primers to a controlled depth within cartridge cases each provided with a face and primer pocket comprising; slide means carried by support means permitting vertical displacement thereof, guide means having a seating recess mounted on said slide means for supporting said cartridge face and including a vertical axial aperture therethrough, means biasing said slide and guide means to a normal upward at-rest position, a plunger adapted to fit within the case and including actuating means for moving said plunger downwardly to press the face of the case against said seating recess against the force of said biasing means, a stem fixedly disposed in axial alignment below said guide means and within said aperture, and fixed control means for limiting the concurrent downward displacement of said plunger, guide means and case, whereby, a primer inserted in said aperture and resting upon said fixed stem will be pressed into the primer pocket of the case an exact distance as limited by the abutment of said guide means against said fixed control means when said plunger is urged downwardly.

2. An apparatus for pressing primers into the primer pocket of cartridge cases, comprising, a pair of vertical pillars mounted upon a support plate, a slide mounted on said pillars for reciprocating movement, means limiting the upward movement of said slide, spring means normally urging said slide upwardly against said limiting means, a plunger supported by said pillars and including actuating means for imparting vertical reciprocating movement thereto to urge downwardly a cartridge case disposed about same, said slide having a guide bushing provided with an upper case seating recess and an axial primer aperture, a stem fixedly disposed beneath said slide and entering said aperture, and stop means on said stem for limiting the downward movement of said guide bushing, whereby, a primer inserted in said aperture and supported upon said stem will be pressed into the primer pocket of the case an exact distance as limited by the abutment of said guide bushing against said stop means when said plunger is urged downwardly.

3. An apparatus for pressing primers into the primer pocket of cartridge cases, comprising, a pair of vertical pillars mounted upon a support plate, a slide mounted on said pillars for vertical reciprocating movement, means limiting the upward movement of said slide, spring means normally urging said slide against said limiting means, a plunger supported by said pillars and including actuating means for imparting vertical reciprocating movement thereto, said slide having a guide bushing provided with a case seating recess and an axial primer aperture, a stem fixedly disposed beneath said slide and entering said aperture, stop means on said stem for limiting the downward movement of said guide bushing, and primer delivery means including a vertical feed tube movable to and from said guide bushing to automatically supply primers singly by gravity to said aperture, whereby, a primer cap inserted in said aperture will be pressed into the primer pocket of the case an exact distance as limited by the abutment of said guide bushing against said stop means when said plunger is urged downwardly.

4. An apparatus for pressing primers into the primer pocket of cartridge cases according to claim 2, including, a transverse top bridge joining the upper portions of said pillars, a drive rod vertically disposed through said bridge for sliding movement therein, means pivotally connecting said plunger to one end of said drive rod below said bridge to permit swinging movement of said plunger from between said pillars, and said actuating means connected to the other end of said drive rod.

5. An apparatus for pressing primers into the primer pocket of cartridge cases according to claim 4, wherein, said actuating means includes a manually operable handle pivotally attached at one end to said bridge and having an intermediate portion thereof pivotally attached to the other end of said drive rod above said bridge.

6. An apparatus for pressing primers into the primer pocket of cartridge cases according to claim 5, and including, spring means between said handle and said bridge normally urging said plunger upwardly to maintain the lower end thereof above said guide bushing.

7. An apparatus for pressing primers into the primer pocket of cartridge cases according to claim 3, wherein, said delivery means comprises, an arm having means mounting same for oscillating movement above said slide, said feed tube is carried by said arm and positioned thereon to overlie said guide bushing aperture upon oscillation of said arm, and a ramp disposed immediately below said feed tube leads to said guide bushing.

8. An apparatus for pressing primers into the primer pocket of cartridge cases according to claim 7, wherein, said arm is mounted upon one of said pillars and oscillates in a horizontal plane, stop means at one end of said ramp limiting the movement of said arm in one direction, said seating recess in said bushing surrounded by a peripheral raised shoulder having a cut-out portion disposed in the path described by said feed tube as said arm is oscillated, and the juxtaposed surfaces of said ramp and seating recess are disposed in a common plane.

References Cited by the Examiner UNITED STATES PATENTS 2,794,359 6/1957 Lyman et al. 8636 2,865,244 12/1958 Doyle 8638 3,110,214 11/1963 Benda et a1. 86 -36 3,153,977 10/1964 Dicken 86-45 BENJAMIN A. BORCHELT, Primary Examiner.

P. A. SHANLEY, Assistant Examiner. 

1. AN APPARATUS FOR APPLYING PRIMERS TO A CONTROLLED DEPTH WITHIN CARTRIDGE CASES EACH PROVIDED WITH A FACE AND PRIMER POCKET COMPRISING; SLIDE MEANS CARRIED BY SUPPORT MEANS PERMITTING VERTICAL DISPLACEMENT THEREOF, GUIDE MEANS HAVING A SEATING RECESS MOUNTED ON SAID SLIDE MEANS FOR SUPPORTING SAID CARTRIDGE FACE AND INCLUDING A VERTICAL AXIAL APERTURE THERETHROUGH, MEANS BIASING SAID SLIDE AND GUIDE MEANS TO A NORMAL UPWARD AT-REST POSITION, A PLUNGER ADAPTED TO FIT WITHIN THE CASE AND INCLUDING ACTUATING MEANS FOR MOVING SAID PLUNGER DOWNWARDLY TO PRESS THE FACE OF THE CASE AGAINST SAID SEATING RECESS AGAINST THE FORCE OF SAID BIASING MEANS, A STEM FIXEDLY DISPOSED IN AXIAL ALIGNMENT BELOW SAID GUIDE MEANS AND 